Prop or brace



Jan. 7, 1947. G. H. JAsPERsEN PROP on nAcE Y Filed May 25, 1945 Ja/C Patented Jan. 7, i947 UNITED STATES ortica 2 Claims.

My invention relates to new and useful `props or braces and one of the objects isto provide .an exceedingly simple, strong, durable and efficient device of this character which may be extended to considerable length and retracted to a relatively small and compact parcel for storage purposes.

The inventiondescribed herein may be used as a prop or brace, either in an upright position or at an angle, with perfect safety and security. The self-locking latch disclosed as a part of the prop or brace will remain secure under terrific pressure and abnormal conditions. The most common use of the invention is as a clothes line prop, however it can be employed safely in different types of Vconstruction Work Where an eXtension prop or brace is needed for adjustment to a number of `different predetermined or Apreselected heights.

Another object ofthisinvention is to construct a propor brace of very lowcost including, in particular, abase section, a free or extensible section and a novel latch that temporarily but positively locks the two sections together in various adjusted positions.

Another object of the invention is to provide a prop-or brace including a self-locking latch so hung that it may be utilized as a brake to retard the descending movements of the extensible section-whenthe latter is permittedto freely fall for retracting Athe same.

A further object of the `invention is to provide a knock-on pin for releasing the latch should the same stick in its locked position.

A still further object of this invention is to provide a self-locking latch in which a number of teeth project laterally from a cross bar, both the cross bar and said teeth being in the same plane.

With the above and other objects in View, this invention consists `of the details of construction and combination of elements hereinafter set forth and then designated by the claims.

In order that those skilled in the art to which this invention appertains may understand how to make and use the same I will describe its construction in detail, referring by numerals to the accompanying drawing forming a part hereof, in which:

Fig. 1 is side elevation of a prop or brace constructed in accordance with my invention and shown in a retracted condition.

Fig. 2 is a similar view illustrating the prop or brace fully extended.

Fig. 3 is a side elevation of the prop or brace on an enlarged scale showing the same retracted and illustrating 'the latch inthe `position for-use as la'brake in dotted lines.

"Fig, 4 is `a viewatrightangles .to Fig. 3.

Figf is a sectiononthelline 5-5 of Fig. 3.

'Fig 6:'is aisection` on' the lineI---By of Fig. ,4.

Fig. 7 ais a fragmentary side elevation .of the prop -or braceY illustrating` a slightly .modified construction ofthe self-locking latch and .how a knock-off pin may be used for disengaging the latch.

Fig. 8 is va'view of :the samefatlright angles to Fig. 7.

Fig. 9 Vis aiperspective view of 4the self-locking latch, the 'form shown in Figs. 3, 4 and 5 being used for this illustration.

AIn carrying out :my invention as .herein embodied `I :employ `abasesection 'Il Aand afree or `extensible section lIfI `.laid .face Ito `face for longithe sections, as the free :section I, by .suitable fastening `devices `I-'l, preferably fby Athrough and through rivets. In order to permit the free or extensible section to freely slide, the portion of the strap which embraces one of the sections, but not fixed thereto, is larger than the cross sectional area of said embraced section. This is accomplished by forming parts of the arms divergent, Fig. 6, and making them longer than the thickness of the embraced section. Stop pins I8 and I9 are mounted on one of the sections, as base section ID, on opposite sides of the strap I4 and in the paths of travel thereof. Said stop pins, preferably, pass all the way through the section on which they are mounted and have both ends exposed for engagement with opposite edges of the arms of the strap. These stop pins are suitably spaced to permit an extensive lengthening of the prop or brace while limiting the movements and preventing accidental displacement of the sections.

The self-locking latch I5 includes a cross barv that said teeth and bar are in the same plane. From the ends of the cross bar 20 extend arms 22, the faces of which are at right angles to the faces of said cross bar and holes 23 are provided in the terminal ends of said arms. These arms are spaced a distance slightly greater than the width of the sections IEI and II and through the medium of said arms the self-locking latch is pivotally mounted on the base section I by means of a rivet 24 projected through said section III and the holes 23 in the arms 22. The latch embraces the free or extensible section II with the teeth extending towards said section II so they may actually penetrate the surface of the section II.

In using the prop or brace, the 4free or extensible section I I is elevated to any desired or preselected height within the limitation of the space between the stop pins I8 and I9. Upon release of the free or extensible section II, its tendency to descend causes the teeth 2I of the self-locking latch I5 to actually bite into or slightly penetrate the material of the free section II, thus securely locking said free section in the adjusted or protracted position. The weight of the free section assures the positive locking of the parts and prevents retracting motion of said free section but the greater the downward pressure, due to additional weight or force on the free section, the

deeper the teeth dig into said free section and therefore the locking eiect of the latch will be proportionately increased. When it is desired to retract the prop or brace, the closed end of the latch is swung upwardly suiciently to disengage the teeth, and the free or extensible section al- I lowed to descend by gravity or said free Section may be controlled by a hand of the user. In order to prevent said free section from descending too swiftly, and possibly damaging some of the parts, the latch may be swung back far enough that the teeth will contact-the free section in a reverse or inoperative position, as illustrated in dotted lines in Fig. 3, and by holding said latch under some slight pressure, said latch will have a braking eiect to retard the descent of the free section. This is highly advantageous when a person has only one hand free and desires to retract the prop or brace, because the ngers may be clasped about the base section and the latch controlled with the thumb.

In Figs. 7 and 8 I have shown a slight modification of the invention wherein the self-locking latch |5a has the arms 22a formed flat with or in the same plane as the cross bar 23a and the teeth 2 Ia, the cross bar and teeth being the same as set forth in connection with the first described latch structure. The terminal ends of the arms 22a are fashioned into bearing loops or eyes 23a for mounting on the pivoting rivet 2da.

A knock-01T pin 25 is shown in connection with the latter structure for illustrative purposes, since it may be left out and the latch used as a brake, or such a knock-olf pin may be employed with the iirst described structure, for the same purpose and with an identical effect. .Said knockoff pin 25 is mounted on the base section slightly above the pivot point of the latch so that the latter can be only elevated to approximately a horizontal position or slightly above such a position, as indicated in dotted lines in Fig. 7.

Where the knock-0E pin 25 is used with either form of latch and the free section is protracted, assuming that said free section is not at its limit of extension, and the teeth stick or retain their engagement with the free section I I, the latch will strike against the knock-off pin and release said latch from the free section of the prop or brace so that said free section may then be moved independently of the base section. If the movement of the free section is outward, as soon as the latch is released it will descend and be in condition for again locking the parts when the outward or upward movement of the free section ceases.

Of course I do not wish to be limited to the exact details of construction herein shown and described as these may be varied within the scope of the appended claims without departing from the spirit of my invention.

Having described my invention what I claim as new and useful is:

1. In a prop or brace, a base section, an extensible section, a strap on the lower end of the extensible section and embracing the base section, and a self-locking latch pivoted to said base section and embracing the extensible section, said latch including a pair of arms lying flatwise against the prop sections, a cross bar having its flat faces in a plane parallel to the axes of the arms, and teeth projecting laterally from the inner edge of the cross bar in the same plane as said cross bar.

2. The prop or brace of claim 1, in combination with a knock-01T pin on the same section that carries the latch and located in the upward path of travel of said latch.

GEORGE H. JASPERSEN. 

